Dispatching and scheduling system



ra Y I i zzzipgno:

Dec. 29, 1936. v c. H. LEVY, JR 2,065,815

DISPATCHING AND SCHEDULING SYSTEM Filed May 25; 1955 5 Sheets-Sheet 1 CAR N=3 2,44 a-m OAR N 2 2-44 Z-HI 2-54 437 2-35 CAR N 4 4441 4'lll LQ OAR N 1 DISPATCH PANEL I114 H" y guy 4, 5 1-54 is 4 H37 1'55" f 9 f4x55 V m5 4-50 p 1'1 IIYH-m l 2-05 3 55 4-55 a E44 ll 1 1v 1 w HG. M INVENTOR BY ATTORNEY Dec. 29, 1936. I c, LEVY, JR 2,065,815

DISPATCHING AND SCHEDULING SYSTEM 1936- c. H. LEVY, JR 2,065,815

DISPATCHING AND SCHEDULING SYSTEM Filed May 25, less 5 sne'ets sneet 3 Fl G. 3 I

M H LpvTghlNVENTOR' ATTORNEY Dec 29, 1936.

C. H. LEVY. JR

DISPATCHING AND SCHEDULING 'sysmq Filed May 25 19:55

F554 5840 4540 D 1-340 2-554 5554 5 +54| L 4-54: E mm 5 1655 -555 155 Dec. 29, 1936. c. H.'LEVY, JR 2,065,315

DISPATCHING AND SCHEDULING SYSTEM Filed May 25, 1935 5 Sheets-Sheet 5 l-S U113 l-suzn rsuw I-SUiI l-SUZIO ATTORNEY Patented Dec. 29, 1936 UNITED STATES DISPATCHING AND SCHEDULINGQYSTEM Oharles Harvey Levy, 317., Maplewood, J.,'alsignor to Otis Elevator Company, New York, N. Y., a corporation of New Jersey Application May 25, 1935, Serial No. 23,368

15 Claims.

-m Such supervisory control may be effected manually or by means of mechanism automaticaiLv operated and controlled. The present invention relates to the exercise of supervisory control over a group of elevators through the medium of such 5 mechanism.

The main feature of the invention is the provision of a supervisory control over a plurality 1 of elevator cars such that the cars are dispatched from a dispatching floor always in accordance 20 with the order in which they approach or arrive at such floor.

Another feature, of the invention resides in the giving of a notification signal to indicate which car is to be the next to leave a dispatching 25 floor, with such signals given in the order of arrival of the cars at that floor, regardless of their order of arrival.

Anotherfeature is to indicate when a car is to leave a dispatching floor by giving a start or 30 dispatch signal for that car, with such signals given in the order of arrival ot the cars at that floor, regardless of their order of arrival.

Other features and advantages will become apparent from the following description and ap- 3 pended claims. a

The invention will be described as applied to a system oi'supervisory control for elevators in which visual signals are employed to indicate.

which car is to be the next to leave the dispatch- 4 1mg floor and when the car which is selected to be the next to leave should depart. The notification or warning signals are given only to cars at the dispatching floor and only to one car at a time. A start or dispatch signal-is given in 45 response to the operation of mechanism which normally operates at regular intervals of time. Provision is made so that if there is no'car at a dispatching floor eligible to be dispatched at the time that a car normally is to receive a dispatch.

50 signal, the giving of .the signal isdelayed until a car arrives at the dispatching floor. In the event that no car arrives at the dispatching floor by the time a given percentage of the time interval has elapsed, operationof the mechanism for giv- 55 mg the dispatch signalsis suspended until a car leaves the dispatching floor. Such operation is preferably had both at a lower and upper terminal floor as dispatching floors. I

In applying the invention to such supervisory control system, both the notification and the dis- 5 patch signals are given to only one car at a time. The cars areselected to receive these starting signals in the order in which they arrived at the dispatching floor regardless of their order of arrival. When a car is selected to be the next to receive a starting signal, the notification signal for that car is given. When the selected car receives its starting signal and leaves, the system becomes efiective incident to the starting of the previously selected car from the dispatching floor to select another car to receive'its starting signal. Regardless of the number of cars which may be at the dispatching floor at the time such selection is made, the cars are selected in the order, in which they arrived at the dispatching In the drawings:-

Figure 1 is a schematic diagram of a four car elevator bank illustrating one relative position of the cars thereof;

Figures 2 and 3, taken together, constitute a wiringdiagram of a dispatching and scheduling system in accordance with the invention;

,Figure 4 is an elevation of a control panel diagrammatically illustrating all the electromagnetic switches, together with the "timingmotor and related equipment, employed in the diagram of Figures2 and 3;

Figure 5 is a view along the line 5-5 of Figure 4, showing details of certain of the relays;

Figure 6 is a view similar to Figure 5, but illustrating the positions of the parts when the actuating coils of the relays are energized; v c Figure 7 illustrates in detail one of the floor selector brushes that is schematicallyfshown in 40 the wiring diagram, and also illustrates in detail a floor selector-contact with which the floor selector brush is in engagement;

Figure 8 is a view of the floor selector brush taken along the line 8-8 of Figure 7:

, equipment, taken alongthe line li-1 .il of Figure 4.

Referring to Figure 1, there is. shown a bank of four elevator cars, cars Nos. I, 2, 3, and 4, operating between two dispatch floors II and I2. These dispatch floors are normally, though not necessarily, the first floor and the top floor. The figure illustrates the position and direction of travel of four cars at one instant in the cycle of events as a convenient starting point for the descriptions of the dispatching and scheduling systems that follow.

There is provided in each car a suitable control panel on which are mounted the various control switches and signals for that car. For simplicity, Figure 1 illustrates the control panel for each car as mounting only operators control switches i-35, 2-35, 3-35, and 4-35 for cars Nos. I, 2, 5, and 3 respectively; up warning lights I-54, 2-54, 3-54 and 4-54 for cars Nos. I, 2, 3, and 4 respectively; up start lights I-I3I, 2-I3I, 3-33? and 4-I3I for cars Nos. I, 2, 3, and 4 respectively; down warning lights I-44, 2-44, 3-, and 4-44 for cars Nos. 1, 2, 3, and 4 respectively; and down start lights I-I I l, 2-I I I, 3-iii, and 4-iII for cars Nos. I, 2, 3,.and 4 respectively.

Suitably positioned so as to be convenient of access for the starter or other ofllcial is a dispatch panel 13 upon which are mounted various hand operated switches and certain other apparatus to control the operation of the dispatching and scheduling system. As illustrated, these include the knife switches 4-50, I-I25, 2-50, i-i25, 3-50,, 3-125, 4-50, 4-I25, 85, 20, 24, 25, 88 and iiii. and the speed control switch 52, all of which are referred to later in more detail. Also mounted upon the dispatch panel 23 or elsewhere so as to be readily visible to the starter or other official is a set of signal lights i-55. 2-55, 3-55, and 4-55 for cars Nos. I, 2, 3, and 4 respectively, at the lower dispatch floor, a set of signal lights I-45, 2-45, 3-45, and 4-45 for cars Nos. I, 2, 3, and 4 respectively, at the upper dispatch floor, and a set of starters signal lights I21 and I25 for the lower and upper dispatch floors respectively.

Suitably positioned so as to be visible to intending passengers in the hall at the lower dispatch floor-preferably over the entranceways to the corresponding cars-are the up hall lights I-53, 2-53, 3-53, and 4-53. In a similar manner, down hall lights.I-43, 2-43, 3-43, and 4-43 are provided in the hall at the upper dispatch floor.

Figures 2 and'3 show a diagram of circuit connections for dispatching and scheduling the four car bank of Figure 1 in accordance with the invention. In this diagram no attempt is made to show the coils and contacts of the various electromagnetic switches in their associated positions, a straight diagram being employed wherein the coils and contacts of the various switches are separated in such a manner as to render the circuits involved relatively simple. The electromagnetic switches have been given letters in addition to the usual reference numbers, so that although the parts of the switches have been separated for simplicity in showing the circuits, they may still be identified by means of the common letters. To aid in understanding the diagram, switches, coils, contacts and other apparatus that correspond for each car have been similarly designated, with the exception of prefixes I--, 2-, 3-, and 4- to'designate the car with which the part is employed. Also, to facilitote the ready location in the wiring diagram of any element referred to in the descriptiom'the reference numbers employed are in numerical sequence (neglecting car identifying prefixes) in that the lowest number (20) referred to in the diagram is at the upper left hand corner of Figure 2, with succeeding numbers following in numerical sequence (as near as practicable) left to right downwardly of the sheet on which Figure 2 appears, and then left to right downwardly of the sheet on which Figure 3 appears. The various elements of the diagram are shown in the positions they occupy when the cars are in the relative positions illustrated in Figure 1, when all knife switches are open, and when all the circuits are disconnected from the power mains. The electromagnetic switches thus are shown in their deenergized positions, so that the contacts thereof that are shown as separated are forward contacts and the contacts that are shown as engaged are back contacts.

The designations of the switches are as follows:

In the diagram of Figures 2 and 3, the relays termed the selective up light relays (SU) and the "selective down light relays" (SD) are of novel construction, and preferably are as illuselectromagnetic trated in Figure 4. The selective up light relays- (SU), one for each car, and associated with events at the lower dispatch floor, are arranged radially about a common center post 205. The selective down light relays (SD), one for each car, and associated with events at the upper dispatch floor, are arranged radially about a common center post 205. The selective up light relays and the selective down light relays are similar in construction and operation, so only the selective up light relays are described in detail. In this description, reference is also made to Figures 5 and 6, which show further details of selective up light relays I-SU, 2-SU, and. 3-SU.

Selective up light relay I-SU for car No. I has its actuating coil I-SUI35 mounted in a U- shsped frame I-SU2II of magnetic material that is suitably secured along its yoke to the vertical control panel 200. At one of the ends of the frame is pivotally mounted, as at I-SU2I I, an armature arm I-SU2I2, preferably of magnetic material. to which is preferably secured a core I-SU2I3 of magnetic material, arranged for movement in and out of a hollow core at the end of the actuating coil; A rearward extension of armature arm I-SU2I2 is subjected to the action of an armsture arm spring I-SU2 I 4 for urging the armature arm to its outward position, as shown in Figures 4 and 5. The armature arm spring is illustrated as a coil spring positioned about a spring rod I-SUI I5 stationarily secured to frame l-8U2 I3, and projecting through a suitable elongated aperture in the rearward extension of armature arm I-SUIH, the spring being positioned between the armature arm extension and a comm nrod. The outward rotation of armature arm i-SU2I2 is limited by the engagement of the armature arm extension with a stop in the form of a'rubber washer l-SUIII positioned on rod I-SU2I5 between the armature arm extension and the frame.

To another extension of armature arm I- SU2 l2 ispivotally mounted. as at I SU2 II, a contact arm l--SU2Z0,'preferably of light material such as aluminum. A rearward extension of thiscontact arm is subjected to the action of a contact arm spring l-SU22| is obtained by providing,

for the washer-securing pin, a plurality of holes in spring rod l-SU222. The outward rotation of contact arm I-SU2I0 is limited by the engagement of a shoulder on the rearward extension of the contact arm with the armature arm, as illusthe movable contact element of contacts.

l-SUI38, while the other contact blade is the movable contact element of contacts'l-SUSG.

The other contact elements of contacts |-SU|38.

and l-SUSB are two contact studs mounted on an insulating block l-'SU224 fastened to frame l-SUHO by means of a bracket l-SU225. The contact blades 01' contacts ISUII8 and ISU56 engage with the contact studs of their respective contacts when armature arm i- SU2I2 and contact arm l--SU220 are each in their innermost positions, as illustrated for relay l-SU in Figure 6. The contact blades are preferably secured to contact block l,-SU223 by means of a pin and spring mechanism as illustrated, that for the contact blade of contacts ISUI38 being designated l-SU226. Since connection may be made to the contact studs and the contact blades in any suitable manner, the conductors by which such connections are made have, for simplicity, not been shown for the relays illustrated. A convenient manner of effecting connection -to the contact blades is indicated, however, in Figure 6 by the dot-and-dash outline of a conductor |.'SU23..

Also mounted on contact arm ISU220 is an inwardly extending shoe i-SU23I of magnetic material. This shoe is so shaped and positioned that when armature arm l-SU2|2 and contact arm l--SU1 2|I are each in their innermost posi-- tions as illustrated for relay 'l-SU in Figure 6, the flat portion of the shoe is adjacent the free end of actuating coil i-SUHG and in the line of magnetic flux between theend of frame l-SU2I0 and the core of actuating coil ISUI36. Preferably, a plate l-SU232 of magnetic material is a portion cut away to clear the core I-SU2I'3.

Preferably also the end of frame |-SU2|0 between the straps is extended so that it is in, the

same plane as the outer. or, as viewed in Figure 5.

the upper surface of plate l-SU2I2. As a result t of this construction, the flat portion of shoe i-SUNI is parallel to, and only slightly displaced from, the outer surface of plate l-SU232 when the parts are in their innermost positions (see Figure 6). When actuating coil l-SUI is energized, the action of the magnetic flux in the region of plate l-SUIII results in attracting the flat portion of shoe l-SUISI thereto, and thus, in moving contact arm l-SU22II to its innermost position and in maintaining it there, with bothcontacts 'l-SUI38 and l.-SU56 in engagement.

Contact arm iSU220 is of such length that its tip engages with center post 206 when the parts are in theirinnermost positions, as illustrated for relay l-SU .in- Figure 6. The center post thus serves as a mechanical stop for the inward motion of contact arm l-SU220.

The selective up light relays (SU) for the other cars are similar in construction to the one just described for car No. I, so a detailed description of them is not made. As already mentioned, these relays are arranged radially about common center post 206, the arrangement being such that the tip of the contact arm for each relay engages center post 206 when the parts of such relay are in their innermost positions, as illustrated for relay I-SU in Figure 6.

As a result oi the above construction for the selective up light relays (BU) it is to be observed that each selective up light relay operates to cause engagement and disengagement of its contacts directly in accordance with energization and deenergization of its actuating coil, so long as, ,while the actuating coil for such selective up light relay is energized, the actuating coil for no other selective up light relay is energized. Thus, under these conditions, when the actuating coil of a relay is energized, the armature arm of such relay is moved to its innermost position. During this motion of the armature arm, the contact arm of such relay moves as though it was a rigid extension of the armature arm-due to the action of the contact arm spring-with the result that the tip of the contact arm sweeps inwardly toward the top surface of ,center post 206. The contact arm of such relay is drawn to its final, innermost position, with the tip of the contact arm in engagement with center. post 208 and with the contacts of such relay in engagement, by the action of the magnetic leakage fluxupon the flat portion of the contact arm shoe. When the actuating coil of such relay is deenergized, the armature arm is returned to its outward position by the action of the armature arm spring. During this motion of the armature arm, the contact arm of such relay moves as though it was a rigid extension of-the armature armdue, as before, to the action ofthe contact arm spring-with the result that the tip of the contact arm sweeps outwardly away from center post 206 and the contacts of such relay are separated.

It is also to be observed, however, that the selective up light relays. (SU) are mechanically interrelated by their contact arms in such a manner tha when the actuating coils for two or more relays" are energized at the same time, the contacts for only one such relay engage and continue in engagement, the contacts for each of the other such relays being positively prevented from engaging. This is illustrated in Figure 6, which illustrates the positions of the parts when the actuating coils for the three relays i-SU, 2--S U, and 3-SU have been, and are maintained,-energized. As therein illustrated, only the contacts of relay ISU are in engagement.

In arriving at the condition illustrated in Figure 6, the actuating coil for relay i-SU is first energized. Relay I--SU thereupon operates in the manner previously described to bring all the parts thereof to their innermost positions. The actuating coil for relay 2SU is then energized. Relay 2--SU thereupon operates in the manner previously described, except that the tip of the contact arm thereof, as it sweeps inwardly toward the top surface of center post 206, engages with the outer surface of the tip of the contact arm of relay ISU, and comes to rest in engagement with such outer surface, in which position the contact arm of relay 2-.SU is not in its innermost position, although it is being continuously urged to such position. Instead, the contact arm of relay 2SU is displaced from center post 206 by the thickness of the tip of the contact arm of relay i-SU. This thickness is relatively small, but is such as to prevent the engagement of contacts 2--SU56 and 2-SU|38 of relay 2-SU. The actuating coil of relay 3-SU is then energized, and this relay thereupon operates in the manner previously described for relay 2-SU, except that the contact arm of relay 3-SU comes to rest with itstip in engagement with the outer surface of the tip of the contact arm of relay 2--SU, in

which position the contact arm of relay 3-SU is displaced from center post 206 by the combined thickness of the tips of the contact arms of relays ISU and 2-SU. Engagement of contacts 3 SUi38 and 3-SU56 of relay 3-SU is thus likewise prevented.

The interdependency of the selective up light relays (SU), characterized by this mechanical piling up of the contact arms about a common point, is thus seen to be effective when two or more relays are in energized condition at the same time. In order to eliminate any jamming of the contact arms of the relays in the event the actuating coils for two or more relays are initially energized at precisely the same instant, the contact arm tips are beveled so that the sides of the tip of each contact arm presents a knife edge to the sides of the tip of each other contact arm.

When the contact arms for two or more selective up light relays (SU) are piled up on center post 206, as described, deenergization of the actuating coil for any relay not on the top of such pile results in withdrawing the contact arm of such relay from its position in such pile without disturbing the other contact arms in such pile, and also results in the return of the withdrawn contact arm to its outward position as illustrated in Figures 4 and 5. Thus, referring to Figure 6, and assuming that actuating coil l-SU|36 of relay iSU is deenergized, armature arm spring I-SU2I4 becomes effective and causes the return of armature arm l-SUIII from its innermost position as illustrated in Figure 6 to its outward position as illustrated in Figures 4 and 5. During the initial portion of such return of armature i-SU2i2, contact arm |SU220 is moved substantially longitudinally away from center post 206, and thus, the tip of contact arm I-SUIZO is withdrawn from under the pile of contact arm tips without disturbing the pile. During the withdrawal of contact arm l-SU22II, there is a small amount of relative motion be-' tween the armature arm and the contact arm, and a slight additional compression of contact arm spring I-SU22I. When the tip of the contact arm has cleared the pile, 1 contact arm spring i-SUHI becomes effective and causes outward rotation of the contact arm relative to the armature arm until the shoulder on the rearward extension of the contact arm engages with thearmature arm. At the termination of the movement of the armature arm and the contact arm, the contact arm is in its outward position as illustrated in Figures 4 and 5.

It is to be observed that when a contact arm is withdrawn from under the pile, the tips of each of the contact arms in the pile that were above the tip of such withdrawn contact arm move inwardly toward the center post a distance equal to the thickness of the tip of such withdrawn contact arm, the relative order of the contact arms in the pile above such withdrawn contact arm remaining the same. Assuming that the contact arm withdrawn is, as with the normal operation of the system herein disclosed, the contact arm at the bottom of the pile (i. c., the contact arm which is in its innermost position, and thus has its contact arm tip in engagement with the center post and has its contacts in engagement), the withdrawal of such contact arm results in inward motion of the tips of each of the other contact arms in the pile a distance equal to the thickness of one contact arm tip. As an incident of this motion, the tip of the contact arm which was in engagement with the tip of the withdrawn contact arm moves inwardly so that the tip of such contact arm is now in engagement with the center post, and its contacts are in engagement. As a consequence, assuming that the actuating coil of each selective up light relay (SU) is deenergized only after the contact arm of such relay reaches the bottom of the pile (i. e., only after the contacts of such rclay engage), the contacts of these relays are engaged successively, for one relay at a time, in the order in which the actuating coils of these relays are energized.

This sequential operation of the contacts of the selective up light relays (SU) may be illustrated by referring to Figure 6. In arriving at the condition shown by that figure-wherein the tips of the contact arms for relays l--SU, 2SU, and 3-SU are piled up on each other in the order stated, starting from the bottom of the pile-it will be recalled that the actuating'coils of the relays were initially energized in the order stated, and that, after initial energization, each actuating coil is maintained energized. As previously explained, only the contacts of relay iSU (contacts I SU|38 and l-SUSB) are in engagement, and the contacts of relay 2-SU (contacts 2-SUI38 and 2-SUS6) and the contacts of relay 3-SU (contacts 3-SUi38 and 3-SU58) are prevented from engaging. Upon deenergizatlon of the actuating coil of relay l'- -SU, the contact arm of this relay is withdrawn and returned to its outward position. The tip ofthe contact arm of relay L-SU thereupon moves into engagement with center post 206, and the contacts of relay 2 -SU (contacts 2- SUHB and 2SU56) are brought into engagement. The tip of the contact arm of relay 3-SU moves inwardly a distance equal to the thickness of one contact arm tip, but in its new position it is still displaced from center post 206 and its contacts are prevented from engaging. Upon deenergization of the actuating coil of relay Z-ASU, the contact arm of this relay is withdrawn and returned to its outward position.

The tip of the contact arm of relay 3-SU thereupon moves into engagement with center post a,oos,sie

of .this apparatus.

3-SUI38 and 3-SU56) are brought into engagement.

' In summary, the construction of the selective up light relays ,(SU) issuch that a sequence is established amongnhe relays depending on the order in which their actuating coils are energized. this sequence being maintained while the actuating coils are maintained energized. Further, it is only when a relay is at the final stage of the sequence, when its contact arm is in the innermost position, that the contacts of such relay are brought into engagement. Thereafter, when this relay is removed from the sequence by deenergizing its actuating coil, the relay next in the succession advances into the final stage of the sequence.

1 A unit comprising a group of two or more relays such as i-SU, etc., arranged about a center post, may thus, if desired, be considered a composite structure and termed a mechanical sequence switch.

In the diagram 01' Figures 2 and 3, certain other apparatus is diagrammatically illustrated that is preferably described separately before undertaking a description of the operation of the complete system embodied in the diagram. In Figure 2 of the wiring diagram, there is diagrammatically illustrated a timing motor 63 connected to suitable reduction gearing 61 to drive a shaft I3. Figure 4 shows constructional details 'The motor 83. suitably mounted upon vertical control panel 200, is arranged above the housing containing the gear ing 67. If desired, the gearing may include a set oi spur gears 240 mounted outside of the housing so that a large range of rotational speeds for the shaft 13 may be readily obtained by the interchange of these spur gears 24!! without disturbing the oil-immersed gearing in the housing. The shaft 13 is provided with contact bridges I4, 94, and I03. The bridges are clamped between the jaws of arms 81, 91, and ii", respectively, from which they are insulated as by means of non-conducting tubes 2. Each arm is adjustably mounted onthe shaft 13 as by set screws, so that the angular spacing between the arms. and thus the contact bridges, may be-set to any desired amount. Figure 11 illustrates one satisfactory angularspacing.

The contact bridges are caused to rotate by the motor 63 in the direction indicated by the arrows in Figures 2 and 11. During the course of this motion, starting from the position in which the contact bridges have been shown, contact bridge I03 engages with a set of stationary contacts I02 and I06; contact bridge 94 engages with a set of stationary contacts 93 and 90, and after one-halt of a revolution of the shaft I3, with a set of stationary contacts 95 and 93; and contact bridge 14 engages with a set of stationary contacts 15 and 82, and after one-half of a revolution of the shaft 13, with a set of stationary contacts 12 andtil. Each set of stationary contacts comprises two metallic fingers of appro priate design (see Figure 11) suitably mounted upon the panel 200. As may be seen, the engagement of each contact bridge with its stationary set'of contacts results in the establishment of a ci cuit between the stationary contacts, and since the contact bridge is normally rotated at a definite speed, as is hereinafter described, the circuit between each set of the stationary'contacts is normally established at regular time intervals.

The wiring diagram diagrammatically illus trates selector brushes l-Il and l-l32 for car No. I, selector brushes 2-H and 2-l32 for car No. 2, selector brushes 3-H and 3-132 for car No. 3, and selector brushes 4-H and 4-i32 for car No. 4, which travel in accordance with the f motions of their respective cars. This correlation of each selector brush with its corresponding car may be effected through the medium of a "floor selector of suitable arrangement in which the selector brush may be mounted upon a travelling crosshead that moves in accordance with the motion of the car for which it is provided. When each car is at the lower dispatch floor, each selector brush for that car engages with a dispatch floor selector. contact individual to that car and brush, and when each car is at the upper dispatch floor, each selector brush for that car engages with a terminal fioor selector contact individual to that car and brush. The selector contacts engaged by selector brushes l-li, 2-ll 3-5l, and 4-5! are contacts 1-52, 2-52, 3-52, and 4-52, respectively, when the respective cars are at the lower dispatch floor, and are contacts l-42,- 2-42, 3-42, and 4-42, respectively, when the respective cars are at the upper dispatch iloor. The selector contacts engaged by selector brushes I-i32, 2-i32, 3-132, and 4-l32 are contacts i-l33,2-i33, 3-i33, and 4-l33, respectively, when the respective cars are at the lower dispatch'fioor, and are contacts i-l2l,

2-i20, 3-l2l, and 4-120, respectively. when the respective cars are at the upper dispatch floor. These dispatch floor selector contacts may be stationarily mounted upon the floor selector at the positions corresponding-to the floors for which they are provided g j I Floor selector brushes l-Il and l-l32 are identical with each other and with the corresponding brushes for the other cars. Floor selector contacts [-32 and i-i33 are identical with each other and with the corresponding contacts for the other cars. A detailed description of floor selector brush l-Sl and of floor selector contact i52 will therefore sumce Floor selector brush i-Sl and floor selector contact 1-32 are shown in detail in Figure 7, the brush and contact for convenience being shown in engagement corresponding to the condition when car No. I is at the lower dispatch floor. Floor selector brush i-Il is mounted upon a travelling member or crosshead l-lll and comprises abraeket l-2ll mounted thereon having a lower arm l-252 and an upper arm l-2I3. A spring piece l-2l4 is secured to lower arm l2l2 and arrangedto extend in the direction of upper arm l-253. A brush l-2ll is secured'to the upper end of spring piece l-2l4,

as by screw l-258, brush l-Ni being of cona brush clip l-Zil having lips which overlapthe spring piece and the brush to prevent rotation of the brush. Brush clip l-IS'I is provided with an extension l-2 58 which projects through 1 an aperturein arm l2l3, extension l-2l3 and such aperture thus serving to limit the outward diagrammatically illustrated direction-distinguishing floor selector switches I-III, 2-I3I, 3-I3I, and 4-I3I for cars Nos. I, 2, 3, and 4, respectively, together with floor bar lugs I-I I9, 2-I I9, 3-I I8, and 4-I I! for causing operation of the respective direction-distinguishing floor selector switches to effect the engagement of contacts I-IM, 2-I20, 3-I30, and 4-I30 of the respective switches. In Figures 9 and 10 are shown the details of direction-distinguishing floor selector switch I-III, such details being the same for the others of such switches. In Figure 9 is also shown the floor bar lug I-IIS. This is the same as the other such lugs, and is shown in Figure 9 in its position relative to direction-distinguishing floor selector switch I-I3I when car No. I is at the upper dispatch floor.

Direction-distinguishing floor selector switch I-I3I is mounted upon the travelling member or crosshead I-250 of the floor selector or equivalent device. Arm I-2III of the switch is pivoted to a U-shaped extension I-2II of a base member I-2I2 of conducting material, the basemember being suitably secured to crosshead I-250, as by the screw I-2'I2 and theterminal stud I-2'I4. Arm I-2'I0 is of conducting material, and has mounted at its upper end, and offset from the body of the arm, one of the contacts I-IIO. Arm I-2I0 is normally maintained in the position illustrated as a result of the action of a spring I-2I5. This spring is interposed between base member I-2'I2 and a lug I-2Ii pivoted at its upper end to arm I-2Il and formed with a lip at its lower end for engaging the edge of an aperture in arm I-2I0 through which a portion of the pivoted lug projects. Such projecting portion of pivoted lug I-2'I0 projects sufliciently outward to engage floor bar lug I-I I9, which is suitably mounted on a floor selector floor'bar I-2I I, as switch I-III'moves past lug I-IIO. The end of arm I-2III below the pivot for the arm engages with base member I-2I2 to limit the outward motion of the arm under the action of spring I-2I5. The lower portion of base member I-2I2 is cut away at the under side thereof, and an insulating block I-2lll is positioned in the recess thus formed and suitably secured to the base member. Block I-2III extends laterally of base member I-212, as illustrated in Figure 10, and to the lateral extension of this block is secured, as by a rivet I-2II, a contact blade I-2l2 and a blade guard I-2II, each of conducting material. The. lower end of the blade guard is provided with a terminal screw I-2l4. To the upper end of contact blade I-2l2 is secured one of the contacts I-IIII and positioned so as to be engaged by the contact I-IIII on arm I-2Il when such arm is moved inwardly.

Inward motion of arm I-2Il, and .thus the engagement of contacts I-Iil, occurs when the projecting portion of pivoted lug I-2II engages with floor bar lug I-I II as the car moves away in a downward direction 'i'rom the upper dispatch floor, and thus, as floor selector switch I-III is moved downwardly from the position illustrat- -ed .'in Figure 9. Under these circumstances spring I-2'I5 maintains the lower lip of pivoted lug I-2I6 in engagement with arm I-2Il. when the car, moving in an upward direction,

approaches the upper dispatch floor, contacts I-I3II do not engage. This is due to the fact that, under these circumstances, as floor selector switch I-I3I is moving upwardly toward the position illustrated in Figure 9, the engag! merit of the projecting portion of pivoted lug I-2I6 with floor bar lug I-l l9, and the continued upward motion of the switch, merely results in the pivoted lug I-2I6 rotating inwardly upon its pivot relative to arm I-2I0, against the influence of spring I-2I5.

The operators control switches I-35, 2-35,

I 3-35, and 4-35 are each provided for controlling the starting of its corresponding car. For simplicity, each control switch shown in Figure 2 of the diagram as provided with only one movable contact (I-26, etc.) and only one stationary contact (I-38, etc.) with which the movable contact may engage upon the throwing over of the operator's control switch to start the car. Connected between the stationary contact (I-38, etc.) for each car and the conductor 30 is the actuatin coil (I-S4I, etc.) of the car starting switch S for the corresponding car. The energization of the actuating coil of the car starting switch for a car causes, among other things, the engagement of the contacts S40 for such car (i. e., contacts I-S4I'I, etc.). These contacts. shown in Figure 2, cause, upon their engagement, and by means of circuits, relays and other apparatus for simplicity not shown, the starting of the corresponding car.

The invention is most readily described by a description of the operation of a system embodying the invention. Such a system is shown by Figures 2 and 3. It is initially assumed that the cars are in the positions and are moving in the directions as shown by Figure l, with the result that the selector brushes I-iI, I-Il2, 2-5I, 2-I22, i-BI, 3-I32, 4-5I, and 4-I32 are in corresponding positions as shown in Figures 2 and 3. It is also assumed that the knife switches I-Bfl, I-I25, 2-50, 2-I25, 2-50, 2-I2i, 4-58. and 4-I25 are closed so that all four cars are included in the dispatching and scheduling system; that knife switches 22, 28, 28, and III are closed; and that knife switch 85 is thrown to the left so that the blades 24 and SI thereof engage the contacts I! and 90 respectively. As a result, upon the closing of the knife switches 20 and 24 to connect the dispatching and scheduling system to the plus and minus mains, the timing motor 83 is started. The circuit for the motor field may be traced from the positive main, through knife switch 20, wire 25, contacts K51 of the timing motor relay, timing motor field 60, wire 24, knife switch 24, to the negative main. The circuit for the motor armature I may be traced from the wire 25, through contacts K51 of the timing motor relay, timing motor armature SI, switch arm 45 of the timing motor speed control switch 82, one of the contacts 04 of the speed control switch, a portion of resistance 66, to wire 20. The speed with which the timing motor runs is dependent upon the amount of the resistance 56 that the speed control switch 62 causes to be included in the circuit just traced. For the arrangement of the resistance 86 as shown, the less resistance that is included in the motor armature circuit above traced, the faster is the speed with which the motor runs The closing of knife switches 22 and 24 also results in the energizatlon of the actuating coil DDIII4 of the down dispatching relay and of the actuating coil UUIIIO of the up dispatching relay. The circuit for the coil DDIII may be traced from the wire 25, through wire I05, coil DDIIN, knife switch 44 (which has been assumed to be closed), to wire 30. The circuit for the coil a,oos,s1s 1 UUI maybe traced from the wire 2', through wire ill, coil UUill3,knii'e switch "I (whichhas been assumed to be closed), to wire 33. The consequent operation of the down dispatching relay DD causes the engagement of its contacts the lower dispatch floors, the engagement ofthe D1310 and the separation of its contacts DDI24. The engagement of contacts DDIII prepares a circuit toithe contacts DH, while the separation or contacts DDl24removes a by-pass around the contacts M22. The operation or the up dispatching relay UU causes'the engagement oi. its contacts UUII and theseparation of its contacts UUI45. The engagement contacts UU'II prepares a circuit to the contacts U'll while the separation of contacts UUI4 removes a by-pass ,around the contacts Ul43.

The closing of knife switches 23 and 24 also results in the energization of the actuating coil Z23 oi the auxiliary down car holding relay and of the actuating coil Y2! of the auxiliary up car holding relay. The circuit for the coil Z23 may be traced from wire 25, through wire 2|, knife switch 22, coil Z23, to wire 33. The circuit for the coil Y2! may be traced from wire 23, through wire 2|, knife switch 26, coil W, to wire 33. The consequent operation oi the auxiliary down car holding relay Z causes the engagementof its contacts Zi03, 2H3, Zll1, and Zl2i. The op.- eration of the auxiliary up car holding relay Y causes the engagement of its contacts Yl4ll, YIN, Y1", and Yllll. As it is assumed that ,at this instant there'are no cars at either the upper or contacts of the auxiliary down car holding relay Z and of the auxiliary up car holding relay Y is oi. no immediate effect.

It is to be observed that, under the above conditions, the actuating coils l-SDI l0, 2--SDl-l3 3SDIIO, and 4-SDII3 of the selective down light relays, and the actuating coils i--SUI38; 2SUi33-, 3-.SUI33, and 4-SUI3I are each deenergized, ,so that all the selective light relays arein their outward positions, as illustrated in Figure 4. I

- Assume that car No. I nowarrives'at the lower dispatch floor. Selector brushes i-5l and i--i32 for that car thereupon engage floor selector contacts l-52 and i-l33 respectively. 'The engagement of selector brush l-l 32 with floor selector contact l-l33 completes a circuit for the actuating coil oi! the selective up light relay SU for car No. I. This circuit may be traced from the 'plus main, through knife switch 20, wire. 25, wire 41, knife switch l-'-i23, .selector brush ll32, floor selector' contact 'l-i33, contacts l-Sl35, actuating coil l-SUI36, wire 28, knife switch 24, to the minus main. 'I'he'selectiveup light relay l-SU thereupon operates. Under the conditions assumed, the selective up light relay SU for each car otherithan car Nol is deenergized, with it's contact arm-in its outward position, so that upon energization-otthe actuating coil l-SUI36 of the selective up light relayfor car No. I, contact arm i-SU220 is immediately moved 'to its innermost position, as illustrated in Figure 6, with the tip oi contact-arm l-SU22-o in engagement with center post 238 and with contacts iSU53 and l-SUI3I in engagement.

The engagement of contacts i--SU55 of the selective up light relay, together with the engagement of selector brush l-Il with floor selector contact i-52, completes a circuit for three signal lights in parallel, i. e., the up hall light i-53, up warning light i54, and starters signal light i-55.

The engagement of contacts l-SU|33 prepares a circuit for the up start light l-I31 for car No. l. Under the assumed conditions oi operation, the circuit for up start light .ll3| is incomplete at the contacts Ui43 and UUI45, so that this light is not now illuminated.

The engagement of selectorbrush i-i3 2 with floor selector contact l-.-l33 also completes a circuit for the actuating-coil l-Al44 or the up car holding relay A, which circuit may be traced from wire 41, through kniie switch i-l25, selector brush I- -l32, floor selector contact l-i33, contacts Yl40, actuating coil |-AI44, to wire 23. Up car holding relay l-A thereupon operates to cause separation of its contacts IA33.. The' separation or thesecontactsserves to prevent energization of actuating coil l-S4| oi the car starting switch for car No. I, and thus serves to prevent the starting of car No. I from the lower dispatch floor.-

Assume that at about this time car No. 3 arrives at the upper dispatch floor. Selector brushes 3-5|' and 3l32 for that car thereupon engage floor selector contacts 3-42 and 3-420 respectively; The engagement 0! selector ,brush 3'-i32 with floor selector contact 3-420 com-y plates a circuit for the actuating coil of the selective down light relay SD for car No. 3. This circuit may be traced from wire 41, knife switch 3-'-l25, selector brush 3-432, floor selector contact 3-l2li, actuating coil'il-SDLHI, to wire 28. The selective down. light relay 3 SD thereupon selective down light relay SD for each car other than car No. 3 is deenergized, with its contact tact arm of relay 3-SD is immediately moved to its innermost position, with its contact arm operates. Under the conditions'assumed, the

- tip in engagement with center; post 205 and with contacts 3-SD46 and .3- SDl'l2 in engagement.

The engagement ofcontacts 3-SD46 of the selective down light relay, together with the-en-.

gagement of selector brush 3-5i with floor selector contact 3-42,; completes a circuit for three signal lights in parallel, i. e., down hall light 4-43, down warning light 3-44, and starters sighal li'ght 3-,45. a The engagement of contacts 3SDil2 preoperation, the circuit for'clown start light 3-Hl is incomplete at contacts Dl22 andDDl24, so that this light is not now illuminated.

down car holding relay B, which circuit 'maybe i traced from wire 41, through'knife switch 3-i25, selector brush 3-i32, floor selectorcontact 3-420, contacts Zl [1,-actuating coil 3-Bl I6,to wire 23. Down car holding relay"3-B thereupon operates to cause separation of its contacts 3B3l. The separation of these contacts serves to prevent energization' of actuating'coil 3-S4io! the carstarting switch for car No. 3, and thus serves to prevent the starting of car No. 3 from the upper dispatch floor;

- The arrival of car No. 3 at the upper dispatch floor is not attended by engagement of contacts 3i3ll oi the direction-distinguishing floor selector switch 3--I3I, for, as previously explained, the pivoted lug on the switch arm, when engaged by the floor bar lug 3-1 I! upon then-- circuit for the actuating coil 3-BH6 oi! the so pares'a circuit for the down start light 3-iil I for car No. 3. Under the assumed conditions of 4 contacts I06 and I02.

rival of the car at the upper dispatch floor, merely rotates inwardly relative to the switch arm.

Assume that after the cars Nos. I and 3 have reached the lower and upper dispatch floors, respectively, as described above, the rotation of shaft 13 by the timing motor causes the engagement of contact bridge I03 with the stationary contacts I02 and I06, and the engagement of contact bridge 94 with the stationary contacts 93 and 96. With the illustrated setting of the arms 91 and I01 which support the contact bridges 94 and I03, the contact bridges engage their respective contacts substantially simultaneously.

The engagement of contact bridge I03 with the contacts I02 and I06 completes a circuit from wire 25, through wire I05, contact I06, bridge I03, contact I02, actuating coil UI00 of the up schedule relay, knife switch IN, to wire 30. This operates the up schedule relay which engages contacts U18 and Ui43. The up sched ule relay is of the type that mechanically latches in after being operated, as illustrated in Figure 4, so that the contacts U18 and UI43 are maintainedin engagement after the deenergization of actuating coil UI00 when the contact bridge I03 subsequently disengages from the stationary The engagement of contacts U18 is of no efieot at the present moment, and their function will be described later.

The engagement of contacts UI43 completes a circuit from wire 41, through knife switch I-I25, selector brush I--I32, floor selector contact II33, up start light I-I31, contacts ISUI08, wire I48, contacts UI43 to wire 20. This causes the illumination of up start light I--I31 for car No. I.

The engagement of contacts UI43 also completes a circuit from floor selector contact II33, through contacts YI40, actuating coil I-AAI4I of the up car releasing relay, contacts I--SUI30, wire I48, contacts UI43, to wire 20. This causes the operation of the up car releasing relay IAA. This relay, upon operation, engages contacts I'AA34 and I--AAI42. The engagement of contacts IAA34 establishes a by-pass around contacts IA33, so that contacts IA33 are no longer effective to prevent the starting of car No. I from the lower dispatch floor. The engagement of contacts I-AAI42 completes a holding circuit for the actuating coil I-AAI4I of the up car releasing relay so that relay I-AA is maintained actuated independently of contacts UI43.

The engagement of contacts UI43 also completes a circuit for the starters signal light I21, traceable from wire 41, through lamp I21 and contacts UI43, to wire 20. The starters signal light I21 is thus illuminated.

The engagement of contact bridge 34 with the contacts 93 and completes a circuit from wire 25, through wire I05, contact 30, bridge 94, contact 93, contact 90, blade 0| of the knife switch 85, actuating coil D01 of the down schedule relay, knife switch 00, to wire 00. The down schedule relay thereupon operates, engaging contacts DH and DI22. The down schedule relay is of the type that mechanically latches in after bein operated, as illustrated in Figure 4, so that contacts 131i and DI22 are maintained in engagement after the deenergization of actuating coil D81 when the contact bridge 94 subsequently disengages from the stationary contacts 33 and 90. The engagement of contacts DH is of no effect at the present moment, and their function will be described later.

The engagement of contacts DI22 completes a circuit from wire 41, through knife switch 3-I25, selector brush 3-I32, floor selector contact 3I20, up start light 3III, contacts 3SDII2, wire H8, contacts DI22, to wire 20. This causes down start light 0-I II for car No. 3 to be illuminated.

The engagement of contacts DI22 also completes a circuit from floor selector contact 3I20, through contacts ZII1, actuating coil 3BBI I4 of the down car releasing relay, contacts 3-SDII2, wire IIO, contacts DI22, to wire 20. Down car releasing relay 3BB is thus operated, engaging contacts 3BB32 and 3BBII5.

The engagement of contacts 3BB32 establishes a by-pass around contacts 3BOI, so that contacts 3B3I are no longer effective to prevent the starting of car No. 3 from the upper dispatch fioor. The engagement 01'. contacts 3BBII5 completes a holding circuit for the actuating coil 3BBII4 oi the down car releasing relay so that relay 3BB is maintained actuated independently of contacts DI22.

The engagement of contacts DI22 also completes a circuit for starter's signal light I20, traceable from wire 41, through lamp I20 and contacts DI22, to wire 20. The starter's signal light I26 is thus illuminated.

Assume that in compliance with the signal given by the up-start light II31, the operator of car No. I closes the car and hatchway doors and moves his control switch I30 into position to start the car. The resultant operation of starting switch I-S etiects not only the engagement of contacts IS40 to cause the starting 01' the car, but also the engagement of contacts ISI34 and separation of contacts I-SI. Contacts l-SI34 complete a circuit for reset coil UI20 oi the up schedule relay. This circuit is through switch I--I25, brush II02, contact I-l33, contacts I-8I34, coil UI20 and contacts UI43. The mechanical latch of theup schedule relay U is thus released and the relay drops back to separate its contacts UI43 and U10. The purpose of the separation of contacts U10 will be explained later. The separation of contacts UI40 extinguishes the starter's signal light I21, advising the starter that the operator oi the car which received the up start signal has thrown his control switch to start position to start the car. The separation of contacts I-SISI breaks the circuit for coil l-SUI30 oi the selective up light relay SU for car No. I. This relay drops back to separate its contacts I-SUI00 and I-SU00. Contacts I-SU I 00 are in the circuit for up start light II31 and coil I-AAllI oi theup car releasing relay, this lamp and coil being maintained energized, however, by way 0! contacts I-AAI42. The separation of contacts I-SU00 breaks the circuit for up hall light I00,'up warning light I04 and starber's signal light I40, causing these lights to be extinguished.

Upon the disengagement of brush II02 from contact I-I33 as the car leaves the first floor, the circuit for up start light I-l01, coil I--AAI4I and coil I-AI44 is broken. The starting light is thus extinguished and up car holding relay I-A drops back, reengaglng its contacts I-All in the circuit for control switch I00. The dropping back of up car releasing relay I-AA to separate its contacts I AA04 is delayed as by a dash pot (see Figure 4) sunlciently to Insure the reengagement or contacts I-A33, thereby preventing the breaking of the teed-*to the control switch.

Assume that in compliance with a signal given by down start light 3-H I, the operator of car No. 3 closes the car and hatchway doors and moves his control switch 3-35 into position to start the car. from the upper terminal floor results in the engagement of contacts 3--I3Ii as floor bar 3- I I3 engages with the projecting portion of direction-' distinguishing floor selector switch 3'I3I. This completes the circuit ior reset coil DI23 oi the down schedule relay, which is from wire 41 through switch 3--I25, contacts 3-430, ,coil DI 23 and contacts DI22 to wire 23. As a result, the mechanical latch 01 the down schedule relay is released so that the relay drops back,separating its contacts DI 22 and D1 I The purpose of -tacts 95 and 33 is open at switch 55.

bridge 34 disengages from the contacts 35 and '33, bridge 14 engages stationary contacts .12 and the separation of contacts D" will be explained later. The separation of contacts DI22 extinguishes the starters signal light I28, advising the starter that the operator of the carthat received the down start signal has left the upper terminal floor."

As'the car continues its motion from the upper terminal floor, brush 3I32 disengages contacts 3I20. This breaks the circuit for the actuatlng coil 3-SDI III of the selective down light relay, which drops back to separate its contacts 3SDI I2 and 3-SD46. The separation of contacts 3SD46 breaks the circuit for down hall light 3-43, down warning light 3-44, and starter's signal light 345, causing these lamps to be extinguished. Contacts -3SDII2 are in the circuit for down start light 3-I II and coil 3-BBI I4 of the down car releasing'relay. However, the circuit for this lamp and coil as well as for coil 3-Bl I5 of the down car holding relay is broken by the disengagement of brush 3-: from contact 3 a- I23. Thus the down start.llght 3I II is extinguished and the circuit to control switch 3-35 is' reestablished through contact 3B3I, the separation oi. contacts 3-BB32 being delayed to insure the maintenance of a feed to the control switch.

' The timing motor continues to run and thus to cause the rotation oi! shaft 13 in the direction.

indicated by the arrow. It is to be noted that with the angular spacing of the mounting arms alter the disengagement of ntact bridgelfl from stationary contacts III and I05 and of contact bridge 34 from stationary contacts33 and 36, contact bridge I4 engages with stationary contacts 15 and 52. This event is of no [eflect under the assumed conditions of operation, however, i'or the circuit through these contacts ter- II, 31, and II" illustrated in gytrisye drawings, soon ,minates at the unengaged contact oil the kniie switch. Subsequently, and after shalt I3 has rotated one-half of a revolution from the position in which bridge 34 was inengagement with contacts 33 and -38, the bridge 34 engages the stationary contacts 35 and 33. This event isalso of no eilect under the assumed conditions of operation, for. the circuit through con- Soon at. This event is also of no eilect, for the circuit through thesecontacts is open at contacts U13 and contacts D! I The next event in time is the reengagement of bridge I03 with stationarycontacts I82 and I05 and of bridge 34 with stationary contacts 93 and 36 as a result of a complete revolution of the upper terminal floor.

The movement of the car away tion is,'a's before, 'oi'no eflect.

gter

' assume that car No. 2 arrives at the lower terminal floor and that car No.- 4 arrives at the A sequence of operations similar to that previously described for car No. I transpires for car No. 2 upon its arrival at the lower terminal floor. The engagement of brush 2---I32 with contact 2-I33 as car No. 2 arrives at the lower terminal completes the circuit for coll 2SUI36 oi the selective up light relay for car No. 2. This relay operates to engage its contacts 2--SU55, completing a circuit through brush 2-5I and stationary contact 2-52 for up hall light 2'53 at the lower terminal, up warning light 2-54 and, starter's signal light 2-55 for elevator N0. 2. Relay 2-SU also engages contacts 2-SUI38, preparing a circuit for .car No. 2 up start light 2l3'l and for coil 2AAI4I of car No. 2 up car releasing relay. The engagement of brush 2-I32 with contact 2I33 also completes a circuit for coil 2-AI44 of car No. 2 up car holding relay which operates to separate its contacts 2--A33 in circuit for control switch 2 -35.

A sequence of operation similar to that'described for car No. 3 transpires when car No. 4 J

arrives at the upper terminal floor. The engagement of brush 4--I32-with contact 4l23 as jcarNo. 4 arrives ,atthe upper terminal coingpletes the circuit for coil 4SDI It or the seleccult for coil 4--BI I5 of car No. 4 down car holding relay, which operates to separate its contacts 4B3I in the circuit for control switch 4.35.

When contact bridge I03 engages contacts III2 and I35, coil UIINI oi the up schedule relay is again energized, and its contacts UI43 and U13 reengage. The reengagement of contacts U13 under the present assumed conditions of opera- The engagement of contacts UI43 completes a circuit for the up start light 2-I3I similar to that previously described for the up start light II3I, and also completes the circuit for the starter's light I2I. The lip start light 2I 31 and the start'ers light I21 are thereupon both illuminated. Start light 2I3I is a signal to' the operator of car No. 2 to leave the lower terminal while the starters light I21 is a signal to the starter that acar at the lower terminal floor has received a signal to Whenthe contact bridge 34 engages with the stationary contacts 33 and 55, which, with the illustrated setting of arms 31 and I", is subnal given by the up start light 2-II'I, the operator of car No. 2 starts his car upward from the lower terminal floor, and that in compliance with the down start light 4I I I the operator of car No. 4 starts his car downwardly from the upper terminal floor. In a manner similar to that described for the starting of car No. I from the lower terminal floor, the operation of control switch 235 to start position causes, through the operation of car starting switch-2--S, the reset 01' up schedule relay U, which extinguishes starters signal light I21, and the energization oi selective up light relay ZAU which, upon droppingeback, breaks the circuit ior up holding light 2-53, up warning light 254 and starters signal light 2-55. The disengagement of brush 2-Il2 from contact 2-433 as car No. 2 leaves the first floor breaks the circuit for up start light 2-HT and for the coils of switches 2AA and I-A. The departure of car No. 4 from the upper terminal floor breaks the circuit for down start light 4-III and for the coils of switches 4-H and 4-33, resets down schedule relay D, which extinguishes starters signal light I28, and breaks the circuit for coil 4--SDI I0 0! the selective down light relay, which drops back to extinguish down hall light 4-43, down warning light 444 and starter's signal light 4-45.

Assuming that the cycle of operations above described continues, car No. 3 is the next to arrive at the lower terminal floor and car No. I is the next to arrive at the upper terminal floor. Further description oi. operation of the system under such conditions is, believed unnecessary. It is believed clear that when a car at each terminal floor is started away with reasonable promptness in compliance with the corresponding up start or down start signal given it, and that before the expiration of the normal time interval after the giving of that start signal (as determined by a complete, continuous revolution or the shalt 13) a car again arrives at each terminal floor, the start signals are given without delay at the expiration of the normal time interval. Under these conditions the start signals are given at regular intervals, and thus there is regularity in the dispatching oi the cars from both terminal floors. The elevator service thus tends to be uniform, for there is normally the same number of cars on the up trip as on the down trip. This relationship among the cars may be termed as having the cars "balanced".

The above described operation 01 the starter's lights 45 and II for each car and starter's lights I24 and I21 assists the starter or other oiiicial in the complete supervision oi the bank oi' elevators. He is informed when a dispatch signal is given by the scheduling device. He is informed all during the time a car is receiving a dispatch signal. He is also informed when the car actually leaves in response to such signal. Thus he I may see whether or not the operators are starting their cars away from the terminal floors with reasonable promptness after they have received the signal to start. In the system illustrated, this supervision extends to both the lower and upper terminal floors. Utilization of the system in conjunction with the indicators that show the positions of the cars in the elevator bank enables the starter to determine which of the cars in the bank is-receiving the starting signal.

Various conditions arise in the operation of elevators which must be met in the scheduling oi. the elevator cars. It may happen, for example, when a car makes more than a normal number of stops during a trip, or when it is delayed for other causes, that the car has not arrived at the terminal floor by the time that it is scheduled to depart therefrom Assume that car No. I has been delayed in its travel toward the lower terminal floor. The engagement 0! contact bridge I" with the stationary contacts I02 and I Iii before the arrival 01 car No. I at the lower terminal floor completes a circuit for the actuating coil UIOII of the up schedule relay as previously described. The resulting operation 0! up schedule relay U causes the engagement of its contacts U'lfl and UI43 and the mechanical latching in of the relay to maintain these contacts in engagement. The engagement of contacts U18 is of no effect at the present moment. The engagement of contacts UI48 completes a circuit for starter's light I21. No other lights are lighted, however, until the car arrives at the lower terminal floor.

Upon the arrival oi car No. I at the lower terminal floor, a circuit is completed for coil ISUI36 01 car No. I selective up light relay by the engagement oi! brush II32 and contact IIll. This relay engages contacts I-SU", completing a circuit for up hall light I-il, up warning light I54 and starter's signal light I---" through brush I5I and contacts I-BI. Thus, the operator of the car is immediately advised that his car is selected to leave the lower terminal and passengers are advised that car No. I is advailable for upward travel. At the same time, the starting light I-ltl is lighted as a resuit of the engagement of contacts I-SUIII oi the selective up light relay, advising the car operator that his car is to leave. The up car releasing relay I-A'A is also operated, permitting the operator to start the car. This situation is maintained until, as previously described, the operator moves his control switch to start position and the car leaves the lower terminal.

A similar operation occurs in the event that a car is delayed in reaching the upper terminal floor. It is believed that this will be understood from the above description, and it will not be described.

In the event that a car gets considerably behind schedule in its arrival at a terminal floor, the system acts automatically to effect a readjustment in scheduling. Assume that car No. I has been delayed in its travel toward the lower terminal floor while car No. I has arrived at theupper terminal iioor substantially according to schedule, and departs therefrom promptly upon receiptoi thestartingsignal. Asaresult,the cycle of events with regard to the delayed car only, car No. I, need be described. The bridging 0! contacts III and I" before the arrival of car No. I at the lower terminal floor causes the operation 0! the up schedule relay U to latch contacts U18 and U! in engagement as previously explained. Contact bridge I then disens les from contacts Ill and I and. with arms I" and ll set as illustrated, soon thereafter contact iridge 14 engages with the stationary contacts II and 02. This event is of no eflect. as the circuit through contacts II and It is open at kniie switch ll. After the disengagement of contact bridge I4 from contacts ll and 82, substantially one-hall ot a revolution of timing shaft-II ensues before bridge 14 engages with the contacts 12 and .0. In the event that car No. I has not reached the lower terminal or, if it has, the contacts K51 in the timing motor feed. Accordingly,

the timing motor stops and the timing shaft 13 ceases to revolve. The timing is thus suspended pending the departure of the car from the lower terminal floor. This suspension aids in the readiustment of the system to the excessive delaying of car No. l, and tends to keep the cars in the desired balanced relation. when car No. I eventually does depart from the lower terminal floor, up schedule relay U is reset, separating its contacts U18. The separation of these contacts breaks the circuit for the actuating coil K16 of the timing motor relay, and so permits the reengagement of its normally engaged contacts K51 to cause the reenergization'of timing motor 63. The timing motor thereupon resumes its operation to cause the rotation of timing shaft 13, and thus to resume the normalv operations of the system.

Assume the condition reverse to that above, wherein with the arrangement of the cars and the system as has been previously described, car No. 3 has been delayed in its travel toward the upper terminal floor, while car No. I has arrived M. This event is of no effect, as before.

at the lower terminal floor substantially according to schedule and departs therefrom promptly upon receipt of the starting signal. As a result, the cycle of events with regard to the delayed car only, car No. 3, need be described. The bridging of contacts 93 and 96 before the arrival of car No. lat the upperterminal floor causes the operation of the down schedule-relay D to latch contacts D11 and DI in engagement as previously explained. Bridge 9| then disengages these contacts and, with arms 91 and 8| set as illustrated, soon thereafter contact bridge 14 engages with the stationary contacts 15 and After the disengagement of contact bridge 14 from contacts 1i and 82, substantially one-half of a revolution of timing shaft 13 ensues before bridge 14 "engages with the contacts 12 and '0. During the course of this one-half of a revolution, contact bridge ll engages with, and separates from, the contacts 55 and 98. This event is of no effect, however, for the section of circuit through these contacts is open at knife switch 85. In the event car No. 3 has not reached the upper terminal or, if :lit has, it has not departed therefrom when contacts 12 and 80 are bridged, the bridging of these contacts completes a circuit for ooil K1. of the timing motor relay. This circuit is through contacts DD", contacts DH and blade 04 of knife switch 85. The timing motor relay operates to stop the timing motor and the timing is suspended pending the departure of the car from the upper terminal floor.- eventually does depart from the upper terminal floor, its departure results in the resetting of the down schedule relay D which breaks the circuit for the actuating coil K18 or the timing motor relay, starting the timing motor in operation again.

When car No. 3'

In the event there is a delay in the departure of cars from both terminals, the timing-is sus- 1 the circuit for the actuating coil K16 is not broken until both contacts DH and U18 are separated. 1

Hence the timing motor relay K is maintained operated to keep the timing motor deenergized until the control switch 35 for the car to depart from the lower terminal is operated to start the car and until a car departs from the upper terminal. p

In the event that a car is late in arriving at a terminal floor, it may be overtaken so that another car arrives at the terminal ahead of it. When-this situation occurs, the overtaking car takes the place of the overtaken car, being dispatched from the terminal ahead of it, so as to minimize any delay in the scheduling of the cars. In other words, the car first to arrive at a terminal is the car first to be dispatched therefrom. This is due to the fact that the operation of the selective up light relay SU for the car first to arrive at the lower terminal interposes the tip of its contact arm SU220 on center post 206 in the path of movement of other contact arms, thereby preventing the engagement of contacts of the selective up light relay for any other car upon the energiz'ation of the coil of this relay as that car arrives at the lower terminal floor. Selective down light relay SD for the car first to arrive at the upper terminal floor interposes the tip' of its contact arm on the center post 205 in the path of movement of other contact arms, thereby preventing-the engagement of contacts of the selective down relay for any other car upon the W nal when it is given.

' nor does the overtaken car receive the start sig- Assume, for example, that the arrival of car No. I at the lower terminal floor is delayed and that it is overtaken by car No. 2, which arrives at this terminal ahead of it. Upon the arrival of car No. 2at the lower'terminal, its selective up light relay 2-SU is operated, lighting up hall light 2-53, up warning light 254 and up starters signal light 2-55, and preparing the circuit for the lighting of start light 2-411. The coil of selective relay ISU is also energized when delayed car No. i arrives at the lower terminal but, as the tip of contact arm 2SU 220 is interposed between center post 206 and; thetip of contact arm ISU220. contacts l,-8U66 and l-SUI38 are not engaged. Thus, uphall light l-il, up warning light l-M and up starters signal light l-fl arenot lighted and. the circuit is not prepared for. start light i-lll. Upon the engagemer t of contacts UNI as a result of ,the operation of the timing mechanism, a circuit is completed for start signal light 2l 31 but not for start signal light l-i31', thereby giving the start signal only to car No. 2.. Also, only the coil of control switch litosta'rt the car, up schedule relay U is reset and coil 2-SUI36 of the selective up light relay for car No. I is deenergized. The deenergization of coil 2-SUI&6 results in the withdrawal of the tip of contact arm 2-SU220, from between center post 206 and the tip of contact arm ISU220, permitting the latter contact arm to engage the center post and thereby close contacts i-SUISB and |SU56. The engagement of contacts ISU56 completes a circuit for up hall light i53, up warning light I-54 and up starter's signal light i55, thereby lighting these lights immediately. The engagement of contacts I-SUI38 prepares a circuit for start light i--i3l so that upon the next operation of up schedule relay U to engage contacts Ul43, as a result of operation of the timing mechanism, the start signal is given to car No. l.

Similar operation is had at the upper terminal floor. Assume, for example, that the arrival of car No. 3 at the upper terminal is delayed and that car No. 4 arrives there ahead of it. Lights 443, 4-44, and 4-45 are lighted upon the arrival of car No. 4 at the upper terminal by the operation of selective down light relay 4SD. Relay 3-SD cannot close its contacts upon the arrival of car No. 2 at the upper terminal because of the interposition of the tip of the contact arm of relay 4SD between center post 205 and the tip of contact arm of relay 3-SD. Thus, lights 3-43, 3-44 and 345 are not lighted. Upon the engagement of contacts DI, the starting light 4i ii is given to car No. 4. The starting signal is not given to car No. 3 because contacts 3-SDI 12 are not engaged. Also, only the control switch 4-35 ic-- car No. 4 is rendered eflfective. When car No. 4 leaves the upper terminal, relay D is reset and coil 44Dl i0 is deenergized. The deenergization of this coil results in the withdrawal of the tip of thecontactarm of relay 4-SD, permitting the engagement of the contacts of relay 3--SD. This causes the lighting of lamps H3, 3-44 and 345 and the giving of the start signal to car No. 3 upon the next operation of the timing mechanism. More than one car may be at a terminal at time for other reasons. For example, the delayed car may not beovertaken but another car may have caught up to it sumciently toarrive at the terminal before the selective light relay for that terminal for the delayed car is deenergized. Or a car may arrive at a terminal at the proper time but a following car may arrive ahead of schedule. In any 'event, the selective relay for that terminal for a second car to arrive at that terminal cannot ei'iect the engagement of its contacts due to the interposition of the tip of the contact arm of the selective relay for the first car to arrive between the center post and the tip or the contact arm of the selective relay for the second car to arrive. The hall lantern. warning signal light and starter's signal light for the second car will not be lighted and the second car cannot be placed in position to receive a starting signal until the deenergization of the selective relay for the car first to arrive at the terminal.

It is preferred to adjust the timing mechanism so that the interval at which cars are dispatched is such that another car does not arrive at the terminal until after a car has lei't. However, this interval can serve only as an average, as traflic conditions affect the operation 0! the cars and may cause them to be late or ahead of time. As a result, it frequently happens that twocars are at a dispatching terminal at the time a start sig-- nal is given to dispatch one of them. Tramc conditions may be such that on occasion three cars .are at a dispatching terminal at the time a startsignal is given, especially where a large number of cars are operating as a group under the supervisory control of the same scheduling mechanism. When more than two cars are at a terminal at the time a start signal is given, it is important that the cars be dispatched from the terminal floor in the order in which they arrived at that floor, as the chances of their being in condition to receive the starting signal in that order is much greater. For example, car No. I may be the one which is about to receive the starting signal from the lower terminal, car No. 2 may be in the process of discharging its passengers at the lower terminal at that time and car No. 3 may arrive at the lower terminal just as the start signal is given to car No. I. If car No. 3 were the one selected to be the next to receive the start signal, it would be delayed in getting away from the lower terminal because it would still have to discharge its passengers before taking on other passengers, whereas car No. 2 would have discharged its passengers and would be ready to receive passengers, thereby being in a condition to get away from the lower terminal without such delay. The schedule relays act to cause the cars to be selected to receive the startingv signal in the order in which the cars arrive at the terminal, thereby minimizing any delay in dispatching the cars from the terminal. This is due to the interposition of the tips of the contact arm of each operated selective relay between the center post and the tip of the contact arm of each subsequently energized relay, thereby piling up the contact arms of the relays in such way that their contacts are made, and the cars for which they are provided are thereby selected to be the next to receive the starting signal in the order in which the cars arrived at the terminal. Furthermore, in this way only one car is made eligible to receive a starting signal at a time, so that only one car is ever dispatched at a time from the terminal floor. 1

The preceding descriptions are all based on the assumption that an even number of cars are in operation. In the event that it is desired to withdraw a car from the control of the system, as, for example, car No. .4,'kni1e switches 4-50 and 4-! are opened. As an odd'number of cars are now under control 0! the system, knife switch ans thrown to the right where its blades 84- and 9| engage contacts and 82 respectively. This change is made so that the odd number of, cars may, be dispatched from the terminals in such way as to obtain a relationship which approaches the balanced relationship obtained with an even number 01' cars. Under such conditions, the dispatch signal tor cars at the lower terminal floor is initiated upon .the engagement 01 contact bridge ill! with stationary contacts I02 and J0. similarly as previously described. The engagement 01' contact bridge 94 with contacts I! and 83 is of no eiiect as the circuit partially completed thereby is open at the unengaged contact 84'. During the course of a revolution oi'.the timing shaft 13 after the engagement of bridge I" with contacts I02 and I", the bridge 94 engages with contacts 96- and 98. This occurs. withthe illustrated setting oi the arms 91 and I01, in the neighborhood oi! hall an interval after the engagement of bridge I" with contacts I02 and I". The engagement of bridge 94 with contacts 05 and 98 completes a circuit through contact I! and blade 9| oi knife switch 45, for actuating coil D" of the down schedule relay. This causes the operation of the down schedule relay and'thus upper terminal floor.

- The throwing of knife switch 86 over to the right also adjusts the time-suspending function of the dispatching and scheduling system to the inclusion of an odd number of cars in the system.

In the event, for example, that a car fails to leave the lower terminal floor during the interval between the engagement of bridge I03 with contacts I82 and I06 and the engagement of bridge 14 with contacts I2 and 88, the timing motor relay K operates similarly as previously described to suspend timing operations. On the other hand, in the eventthat a car fails to leave the upper terminal floor during the interval between the engagement of bridge 94 with contacts '96 and 88 and the engagement of bridge 14 with contacts 16 and 82, the engagement of bridge 14 with contacts 16 and 82 causes the operation of the timing motor relay K to suspend timing operations in a similar manner. The circuit for the coil of the timing motor relay K is throughlcontacts DB",

contacts. Dll, blade 84, contact 86, contacts 15 and 82 and coil K18.

Accordingly, it is believed clear from the foregoing that any number of cars may be made subject to the control of the dispatching and scheduling system upon the closing of the knife switches 50 and I25 foreach car to be included in the system, and the throwing of knife switch 85 to the left or right depending upon whether the total number of cars included is even or odd.

During certain times of the day, as for example, in the morning, the passenger traiiic'may be predominantly from the lower terminal floor upinto the building. Under these circumstances it. may be desirable to reduce to a minimum the period during which a car may be at the upper terminal floor waiting for the expiration of the scheduling interval after the giving of the down dispatch signal to the preceding car. In such eventthe starter may open'knife switch 88. As a result the actuating coil DDI 04 of the down dispatching relay is deenergized, thereby effecting the engagement of its contacts DDI and the separation of its contacts DDlii. The engagement of contacts DDI establishes a by-pass circuit across the contacts Dl22 of the down schedule relay D so that the eifect is the same as if these contacts of the down schedule relay were maintained in engagement. Accordingly, as soon as a car arrives at the upper terminal floor and its selective down'lightrelay SD operates, the circuit through its down start light III is complete so that the car receives the down dispatch signal immediately. The separation of contacts DDIO renders thetiming suspension function inoperative for the upper terminal floor so that, with the actuating coil D8! of the down schedule relay also inoperative as a result of the opening example, in the evening, the passenger trafllc may' be predominantly from the upper floors of the building down to the lower terminal floor. Under these circumstances it may be desirable to reduce -to a minimum the period during which a car may be at the lower terminal floor waiting for the expiration of the scheduling interval after the giving of the up dispatch signal to the preceding In such event the starter mayi openknife switch II. This gives the same result forthe lower terminal as the opening of switch 88 gives m the upper terminal. Coil com is deenergized, separating contacts UUI'I and engaging contacts UUI. A by-pass circuit is established by contacts UUHS across contacts Ulll of the up schedule relay U. Accordingly, as soon as a car arrives at the lower terminal floor and its selective up light relay SU operates, the circuit through its up start light Ill is complete so that the car receives the up dispatch signal imme-.

diately. The timing-suspension function for the lower terminal floor is rendered inoperative by the separation of contacts UUll so that continued rotation of timing shaft I3 is of no effect so far as the lower terminal floor is concerned.

It, is to be noted that in the event that the passenger traffic becomes extremely heavy, the starter may dispense with the scheduled interval between cars at both terminal floors by opening both knife switch 88 and knife switch illl. As a result each car receives the signal to start as soon as it arrives at a terminal, floor and its selective light relay for that floor operates. In this manner the cars may be operated to give maximum service during peak traffic conditions.

In the event it is desired not to prevent the departure of the cars from the lower and upper terminal floors until the receipt by the cars of the dispatch signals, the knife switches 26 and 22 may be 'opened.. As a result, coils Y21 and Z23 are deenergized and contacts Y|48, Yi46, Ylll, and Yiiil, and contacts Zl09, ZII3, Zlll, and Zl2l each separate to prevent the energiza tion of the two actuating coils of both the up and down car holding relays for each car. If it is desired to prevent the departure of the cars from only the lower terminal floor until the receipt by the cars at that floor of the dispatch signals, only knife switch 26 maybe closed so that only the up car holding relays are rendered effective, If it is desired to prevent the departure of the cars from only the upper terminal floor until the receipt by the cars at that floor of the dispatch signals, only knife switch 22 may be closed so that only the down car holding relays are rendered effective.

It is to be noted that the scheduling interval may be lengthened or shortened by the adjustment of the speed control switch 62. This switch, as previously explained, regulates the speed with which the timing motor 63 runs, and thus the speed with which the timing shaft 13 rotates.

It is also to be noted that the arms 8|, 9! and I! may be set on the timing shaft I3 at other angular relationships than those shown. For example, the arm 8| may be reset so as to increase or decrease the predetermined time after the operation of a schedule relay before the timing is suspended, in the event that no car has departed during that time. In addition, the arms H11 and 91 may be set with an appreciable angular relationship between them. The effect of this latter change is to vary the relationship between the time allowed foran up trip and the time allowed for a down trip.

, It may thus be seen that the dispatching and scheduling systemsas provided by this invention are capable of operating readily under numerous and various operating conditions that arise in elevator systems.

Attention is directed to the fact that when the cars are being dispatched at regular time intervals, the car eligible to receive the next dispatch signal from the lower or upper terminal floor may be-ordered-to start therefrom, without waiting for the expiration of the scheduling interval, by opening the kniie switch III for the lower terminal floor, or knife switch 88 for the upper terminal floor. This operation is due to the previously explained by-pass circuit formed around the schedule relay contacts Ul 43 or DIN.

It is to be understood that, it so desired, audible signals may be used in place of visual signals, or audible signals may be used in addition to visual signals. In either case, the audible signals may be single stroke or continuous stroke 8 85.

It is also to be understood that if desired the selective relays may be deenergized and the schedule relays reset in other ways. For example, the down schedule relay D may be reset in response to operation of a control switch 35 to start a car from the upper terminal. I Also, the selective down light relays may be deenergized in response to operation of the respective control switches to start the cars for which they are provided from the upper terminal. It may be desirable to provide two brushes on each selector, one for cooperating with contact I20 and the other for cooperating with contact in, instead of one brush B2, and to render the respective feed wires to these brushes subject to direction contacts, with the brush for cooperating with contact I33 eil'ective only when the up direction interlock contacts are closed and with the brush for cooperating with contact I20 eiiective only when down direction interlock contacts are closed. 0n the other hand, the-selective relays for both the upper and lower terminal floors may be deenergized by disengagement oi their respective brushes I32 from contacts I33 and IN, instead of deenergizlng the up schedule relays by operation of control switches 35. Also, each up schedule relay U may be reset by an arrangement similar to that shown for resetting each down schedule relay D, with each switch ill employed to complete the circuit for coil Ulil closed only as the car for which it is provided leaves the lower terminal on an upward trip.

The construction 01 the mechanism comprising the selective relays may be modified and other arrangements may be employed to cause the cars to be selected toreceive their starting signal in the order in which they arrive at a dispatching floor. Also, various forms 01 mechanism actuated in accordance with car movement may beutilized to control the lighting of the hall lights, warning lights and starters signal lights and to control the operation 01 the selective relays, starting lights and schedule relays.

It is apparent that the floor selectors may be arranged so that the engagement of their brushes and contacts, for example brush l-lfl and contact l-lfl oi the floor selector for car No. I, oo-

curs Just as the car reaches the exact floor level or so that the engagement occurs in advance of the car reaching the actual floor level. This advance might be a matter of several feet, depending upon the requirements 01 the particular installation. It is therefore not intended that the term arrive at a floor, as used in the speciflcatlon and claims, be restricted in its meaning to the car having reachedthe iloor.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a dispatching and scheduling system for a plurality oi elevator cars, not less than three, wherein each car is started from a dispatching floor upon receipt of a starting signal for that car; mechanism adapted upon each operation to cause the giving oi a starting signal; means ior causing said mechanism to operate at regular time intervals; and means for causing the order in which said starting signals are given to be in the order in which said cars arrive at said dispatching floor, regardlessoi' the number oi said cars at said dispatching floor at the time a starting signal is given to one of such cars, and regardless oi the order in which such cars arrive at said dispatching floor.

2. In a dispatching and scheduling system for a plurality of elevator cars, not less than three; a dispatching floor; a starting signal for each of said cars; mechanism adapted upon each operation to cause the giving of one oi said starting signals; means for causing repeated operations of said mechanism; and means for causing the starting signal given in response to each operation of said mechanism to be for a car positioned at the dispatching floor and for causing the order in which said starting signals are given to be in the order in which said cars arrive at said dispatching floor, regardless of their order of arrival or of the number which are at said dispatching floor at the time that a starting signal is given.

3. In a dispatching and scheduling system !or three or more elevator cars; a dispatching floor; a starting signal for each of said cars; switching mechanism operable to cause the giving of a starting signal to a selected one of said cars; means for causing said switching mechanism to operate at regular intervals oi time; and means for selecting the car to which a starting signal is given in response to each operation 01' said switching mechanism to be a car which has arrived at said dispatching floor, said selecting means being rendered eil'ective, incident [to the response of a car to the last starting signal given, to select the car to which to give a starting signal upon the next operation of said switching mechanism, and said selecting means acting, when two or more cars other than the one to which a starting signal has been given are at the dispatching floor at the time it is rendered eilective to select the next car to receive a starting signal, to select that oneoi such cars which was the first to arrive at said dispatching iloor.

4. In a dispatching and scheduling system for three or more elevator cars; a dispatching door; a starting signali'or each of said cars; switching mechanism operable to cause the giving oi a startingsignaltoaselected oneotsaidcars: operating means for, causing said switching mechanism to operate at successive predetermined intervals of time; a relay for each car; means for each car actuated in accordance with movement thereof for operating said relay for that car upon arrival of the car at said dispatching floor, said relay. upon operation, selecting that car to be the one to which a starting si ns! is given in response to an operation of said switching mechanism: and mechanism interlocking said relays so as to suspend the operation of a relay to select its car iorreceiptofitsstartingflt luntilthecar which arrived at said dispatching floor next ahead of that car has received its starting signal and the relay for such car released; and means for releasing each relay after the starting sigual mechanism operable to cause the giving of a starting signal to a selected one of said cars; 'opstarting signal to a selected one ofsaid cars; operating means for causing said switching mechanism normally tooperate at successive predetermined intervals of time; an electromagnetic switch for each car, each switch being adapted upon energization to operate contacts to select the car for which the switch is provided to be I the one to which a starting signal is given in response to an operation of said switching mechanism; means for each car for energizing said switch for that car upon arrival of the car at said dispatching floor; means associated with each switch and acting upon energization thereof to thereafter prevent the operation of said contacts of the switch for each car which arrives at the dispatching floor subsequent to the arrival thereat of the car for which that switch is provided until that switch is deenergized'; and means operable incident to the starting of each car from said dispatching floor uponreceipt of its starting signal for deenergizing said switch for that car.

a starting signal for each of said cars; switching mechanism operable to cause the giving of a erating means for causing said switching mechaa nism to operate at successive predetermined intervals of time; a plurality of relays, one foreach car, each relay having contacts adapted, upon engagement, to select the car for which the relay is provided to be the one to which a starting signal is given in response to an operation of said switching mechanism; means for each car for causing energization of said relay for that car upon arrival of the car at said 'dispatching floor; mechanism for interlocking said relays-so as to prevent the engagement of the contacts of each energized relay until the next previously energized relay is deenergized, thereby to prevent the giving of a starting signal to more than one car at a time and to cause the starting signals to be givenin the order of arrival of the cars at the dispatching floor, regardless of their order of arrival orof the number of them which may be at the dispatching floor at any time; and means operable incident to the starting of each car from said dispatching floor upon receipt of its starting signal for deenergizing said relay for that car. 7

'7. In a dispatching and scheduling system 1dr three or more elevator cars; a dispatching floor;

a starting signal for each of said cars; switching mechanism operable to cause the giving of a starting signal to a selected one of said cars;

operating means for causing saidswitching be the one to which a starting signal is given in response to an operation of said switching mechanism, and each relay having an arm adapted upon energizatlon of the relay to interpose itself between the center post and, the arm of each subsequently operated relay thereby to prevent the at said dispatching floor; 6. In a dispatching and scheduling system ior A three or more elevator cars; a dispatching .floor;

engagement of the contacts or each relay until the arms of all previously energized relays are withdrawn; means for each car actuated in accordance with movement thereof for causing energization of said relay for that car upon arrival of the car at said dispatching floor; means operable incident to the starting-oi each car from said dispatching'floor upon receipt of its starting signal for deenergizing said relay for that car; and biasing means for each relay operable, upon deenergization of that relay to separate the contacts of the relay and also to withdraw said arm of that relay from said center post to permit the engagement of the contacts of the relay for the car next to arrive at said dispatching floor,

thereby to cause the starting signals to be given in the order of arrival of the cars at the dispatching iloor, regardless of. their order of arrival or of the number'of them which may be at the dispatching floor at any time.

8. In a dispatching and scheduling system for three or more elevator cars;fa dispatching floor; a plurality of notification signals, one for each of said cars, for indicating which car is to be the next to leave. said dispatching floor; means for each car for causing the giving of the notification signal for that car upon arrival of the car and interlocking mechanism for preventing thegiving of a notification signal for morethan one car at a time and. to cause said signals to be, given in the order of arrival of the cars at the dispatching floor, regardless of their order of arrival or the number of them which are there at a time.

9. In a dispatching and scheduling system for three or more elevator cars; a dispatching floor; a plurality of notification signals, one for each of said cars, for indicating which car is to be the next to leave said dispatching floor; meansfor each car for causing the giving of the notification signal for that car upon-arrival of the car at said dispatching floor; interlocking mechanism for preventing thegiving of a notification signal for more than one car at a time and to cause,

said signals to be given in the order of arrival of the cars at the dispatching floor, regardless of their order of arrival or of the number of them which are there at a time; and means operable incident lJO BhB starting of each car from said dispatching floor for rendering said interlocking mechanism effective to permit the giving notification signal to another car. i

10-. In a dispatching and scheduling system for three or more elevator cars; a dispatching floor; a plurality of notification signals, one for each of said cars, for indicating which car is to be the next'to leave said dispatching floor; a plurality of relays, one foreach car; means for each car actuated in accordance with movement thereof for operating said relay for that car upon arrival of the car at said dispatching floor, each relay, upon operation, acting tocause the giving of the notification signal for the car for which the relay is provided; and mechanism for interlocking said relays so as to render each relay ineifective to cause the giving of the notification signal for the car for which the relay is provided, until all the relays for all cars arriving at said dispatching floor ahead of that car have been restored to unoperated condition, thereby to prevent the giving of a notificationsignal for more than one car at a time and to cause said signals to be given in the order of arrival Qf the cars at the dispatchingfloor, regardless of their order of arrival or of the number of them which are there ofa" 

